WITH table1 AS (
    SELECT
        PO.PF_CODE AS"都道府県コード"
        ,PF_NAME AS "都道府県名"
        ,sum(case when PO.SURVEY_YEAR = 2015 then TOTAL_AMT else 0 end) AS "総人口2015年"
        ,sum(case when PO.SURVEY_YEAR = 2020 then TOTAL_AMT else 0 end) AS "総人口2020年"
    FROM
    POPU_TRANSITION AS PO
    LEFT JOIN 
       PREFECTURE AS PR
    ON 	PO.PF_CODE =PR.PF_CODE
    GROUP BY 
      PO.PF_CODE)
SELECT 
   *
   ,ROUND(CAST("総人口2020年" AS float)/CAST("総人口2015年" AS float)*100,0)+'%' AS "人口増加率"
FROM table1
WHERE 
    "総人口2020年" > "総人口2015年"
ORDER BY
    "人口増加率" DESC
    ,"都道府県コード" ASC;